As strange as it sounds, the Ulster Volunteer Force (UVF) was distrustful of pro- and anti-Treaty forces. They disliked the pro-treaty Irish Free State government because they suspected that this government had hidden pro-Northern IRA sympathies. Conversely, the UVF membership also did not like the anti-Treaty forces because the anti-treaty factions did not want a separate Northern Irish state.

As of 1920, when the cease-fire was in place and a treaty was in the making, the UVF ground to a standstill but was were establishing a foothold within the newly forming Northern Irish government, especially the Ulster Special Constabulary (USC) which was a quasi-military security force. At this point, the newly formed Royal Ulster Constabulary (RUC) also drew quite a few members from the UVF. In theory, the UVF should not exist because of the ceasefire, but there still about 3000 UVF members still active in loyalist groups like the Orange Order. These self-proclaimed UVF men were hostile to the Treaty and its supporters. For example, UVF members were highly active in the various riots that rocked Belfast in the 1920s. Most of these riots were highly sectarian and targeted Catholics.

Ultimately, the official UVF line is that they were going to join the state and abide by the Treaty. However, there was a small, but strong, group of UVF fanatics who brook no compromise. In the meantime, the influx of UVF members into security and police forces as well as within political offices accentuated the sectarian structures within the Northern Irish state. For example, Lord Londonderry had trouble passing a non-sectarian education bill in the 1930s because of this strong pressure group (and the Catholics in Northern Ireland were also opposed the bill). The UVF reflected some of the larger sectarian issues in the formation of the Northern Irish state. They accepted the Treaty, but they were suspicious of those trusted to enforce it and the UVF membership acted accordingly.

Sources

Bowman, Timothy. Carson's Army: The Ulster Volunteer Force, 1910-22. Manchester: Manchester University Press, 2007.

Farrell, Michael. Arming the Protestants: The Formation of the Ulster Special Constabulary and the Royal Ulster Constabulary, 1920-7. London: Pluto Press, 1983.